Initial reports of the eruption came from crews on four separate ships.

Scientists remain unclear if the emissions are gas or lava.

“The eruption takes place amidst an unprecedented earthquake swarm in El Hierro. The number of earthquakes recorded since July 17, 2011 on El Hierro has now exceeded 10,000.”

Hierro, a shield volcano, last erupted in 1793. The eruption, which produced lava flows, lasted approximately one month.

Although government authorities have suspended ferry activities to and from the 285 square-km island, and have recommended that boats should not sail closer than four miles off El Hierro, and have warned divers to suspend all activities, the estimated 11,000 residents of El Hierro were being reassured not to be alarmed.

2 thoughts on “Underwater Volcanic Eruption Underway Near El Hierro”

Spain’s Instituto Geográfico Nacional (IGN) confirmed on Tuesday that an underwater eruption has occurred five kilometres off the southern coastline of El Hierro, the smallest of the Canary Island. The eruption is Spain’s first since the eruption in 1971 of the Teneguía volcano on the island of La Palma (Canary Islands).
The IGN says all three of its seismic stations on El Hierro in the Canary Islands have registered a volcanic tremor of low frequency in the south of the island at La Restinga, the southern-most village in the Canaries. The estimated 537 residents of the town were summonsed to a local football field on Tuesday afternoon to be briefed on evacuation procedures.
A Red Alert has since been issued by local authorities for the town. A notice posted on the Emergencia El Hierro website on Tuesday evening stated: “Phase pre-eruptive. It involves the initiation of a preventive evacuation. Make yourself available to the authorities.”
Spanish Prime Minister José Luis Rodríguez Zapatero and cabinet colleagues will attend an emergency briefing on the developing situation on Tuesday evening.
Scientists from IGN and CSIC (Consejo Superior de Investigaciones Científicas), meanwhile, have conducted a reconnaissance flight over the sea to the area south of the island, where they have located dead fish floating on the surface five kilometres from the coast. The dead fish were identified in an area where lower seismic magnitude occurred on October 9, at a depth of approximately 2 km.
The present volcanic activity is understood to be occurring at a depth of 600 metres (just under one kilometre) below sea level, in the Las Calmas sea.

2 new eruption locations have been detected this afternoon. The eruption sites discovered today are much nearer to the coast than the initial location at 5 km out of the La Restinga coast.
Today’s most remote location is at a depth of 750 meter and 2 nautical miles out of the coast. The second at a depth of 500 meter and 1.5 nautical miles from the coast. (1 nautical mile = 1.85 km)

Authorities told the press that fissures has been opened which resulted in green water spots with a strong sulfurous odor. Just like Monday a lot of dead fish have been detected at the surface waters too.

Scientist are hoping that the present submarine eruptions will decrease the pressure on the main island and are hopeful that the tremors will weaken.
The new fissures have been opened when we reported the strong change in seismicity during the afternoon.